Extended s-wave altermagnets

Matteo Dürrnagel; Lennart Klebl; Tobias Müller; Ronny Thomale; Michael Klett

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arXiv · 2508.20163

Extended s-wave altermagnets

Matteo Dürrnagel·Lennart Klebl·Tobias Müller·Ronny Thomale·Michael Klett

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Abstract

We propose extended s-wave altermagnets (sAMs) as a class of magnetic states which are fully gapped, spin-compensated, and feature spin-polarized bands. sAMs are formed through valley-exchange symmetries, which act as momentum-space translations beyond standard crystallographic spin-group classifications. Using an effective two-valley model, we demonstrate that sAMs exhibit isotropic spin splitting, enable spin-selective transport in tailored heterostructures, and give rise to descendant pair density wave order. From a microscopic sAM minimal model, we develop the guiding principles to identify sAMs in quantum magnets.

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Matteo Dürrnagel, Lennart Klebl, Tobias Müller, Ronny Thomale, Michael Klett. 2025-08-27. Extended s-wave altermagnets. https://arxiv.org/abs/2508.20163

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